“Refire” Kits Not an Option for US Army

When a Cartridge Actuated Device (aka “CAD” or “squib”) on the hoist is fired, ALL the components of the cable cut system must be replaced – the squib and o-ring, cable, cable cutter and o-ring, cable cutter cotter pin, and anvil…as well as potentially some shims from the KT-444 shim kit (aka “clocking kit”). The hoist manufacturer, Breeze-Eastern, sells all of these parts together as a kit called the KT-493 Refire Kit. While this is convenient, it is a bit of a problem for Army users because the Army treats and tracks squibs the same way that ammunition and other…
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Static Discharge Cable Removed from AWR 980

A number of years ago, based on numerous requests from the field, the #415 Static Discharge Cable (manufactured by Lifesaving Systems Corporation (LSC)) was added to AWR 980. This cable can be used to dissipate the static discharge that is sometimes experienced during hoisting operations. Since then, there have been requests about similar products made by other manufacturers. The decision was recently made to remove the static discharge cable from AWR 980 – not because it can no longer be used, but because its use does not require an AWR to begin with. It does not have an ON/OFF switch,…
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Now Offering Zephyr Training

Now Offering Zephyr Training

In coordination with Zephyr International LLC, Vertical Lift Consulting is now offering training for the Zephyr Rescue Hoist Ground Support Equipment (RHGSE). Training is available for this equipment in one of two ways: On-site at the manufacturer’s location in Conway, SC.Off-site where we bring the training to you. Our training will mirror the 2021 On-Site curriculum for Zephyr International, which is now limited to one day with a maximum of ten (10) students. The 2021 schedule for on-site classes is as follows: Thursday, 28 JANThursday, 15 APRThursday, 24 JUNThursday, 26 AUGThursday, 28 OCT You can register for these classes or…
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Update on Hoist Cable Set Screws

What is the purpose of the cable set screw? You know…that small screw that gets torqued to 10-12 in-lbs after installation of a new hoist cable? Let’s start off by saying what IS NOT the purpose of the screw. It IS NOT the purpose of the screw to hold the rated load of the hoist (600 lbs). If that WAS the purpose, it would need to be a much larger screw, indeed! So, if it is not the purpose of the set screw to hold the load, then what IS its purpose? The purpose of that screw is simply to…
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Cable Reseat vs Post-Operational Check…one defeats the other?

You completed hoist operations for the day and concluded your flight with a cable reseat of 150 lbs. After shutdown, the aircraft was towed into the hangar and, per the required Post Operational Check in the Army checklist, the “amount of cable used” was reeled out in order to inspect it for “corrosion, kinks, separated strands, wear, and broken or frayed wires.” Question: "What good did a reseat do for me if I’m just going to follow it up with a cable inspection that leaves loose wraps on the drum?" That’s a very good question and one that has been…
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Tagline Techniques, Part 1

Taglines are used to minimize spin, swing, and oscillation (conical rotation) of hoist devices. Spin is an issue because the hoist hook has a swivel bearing. That swivel bearing is a must so that torsional forces in the cable (above the hook) can depart the system. Without it, the cable would unravel. An unfortunate by-product is that everything below the hook can also rotate and that can present its own challenges. Spin typically results from the effects of air movement (e.g. wind or rotor downwash). A suspended object will rotate so as to present its smallest surface area to that…
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30° Fleet Angle Limitation on the Hoist

Continuing along the same lines as previous articles related to controlling cable swing or oscillation, this article discusses an actual limitation for hoist operations – a maximum 30-deg fleet angle. Army users will be familiar with the -10, Chapter 5, angle of bank limitation while maneuvering with a rescue hoist load: 30 degrees. But where is the hoist fleet angle limitation stated? Not in Chapter 5. In fact, it is not in the -10 at all so it is often missed. Where do we find it? In the TM work packages under functional characteristics for the hoist, and in the…
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Controlling Hoist Oscillation – Advanced Techniques

We previously published an article entitled, “Controlling Hoist Oscillation – It’s All About Cable Length.” Be sure to read that article before this one. In that article, we discussed the basics of pendulum control. We introduced a pendulum simulator known as the PhET simulator from the University of Colorado, Boulder – a great online tool that allows users to experiment with controlling pendulum movement. We noted that changing the weight of the object has absolutely no effect on the oscillation. However, changing the length of the cable does affect oscillation and that effect can be significant. In fact, the greater…
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Four-Strand LUE #3 Underway at NTC

The third Limited User Evaluation (LUE) for the Four-Strand cable is well underway in the middle of the Mojave Desert, with the US Army Air Ambulance Detachment from the National Training Center (NTC) hosting the event. Phase I of the evaluation was completed 23-25 JUL 2019 by C Co, 2916th Avn Bn, Ft. Irwin, CA. Phase II of the evaluation will run for 90 days. The new hoist weight system (aka, “lift bag kit”) is also featured in some of the photos below. [wonderplugin_gridgallery id=10]
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Controlling Oscillation – It’s All About Cable Length

“Spin,” “swing,” and “oscillation” – what’s the difference? When it happens, is there anything I can do about it? Good questions! And knowing the answers to those questions can mean the difference between life and death. A spin is the rotation of an object around the long axis of the cable. Considerable rotational forces are generated whenever the cable is placed under tension or when the length of the cable changes. We have a swivel bearing at the end of the cable to assist in relieving those forces. The downside to that is that anything below the swivel bearing is…
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